65 research outputs found
Evaluation of the possible protective role of naringenin on gentamicin-induced ototoxicity: A preliminary study
Objectives: The purpose of this study is to evaluate the possible protective role of naringenin in gentamicin-induced ototoxicity through an audiological, biochemical and histopathological evaluation. Methods: This study was conducted on 32 adult male rats that were randomized into 4 groups(control, gentamicin, naringenin + gentamicin, and naringenin). Naringenin was given to the rats via oral gavage in a dose of 50 mg/kg/day during the 14 day study period. Gentamicin was given by the intraperitoneal route in a dose of 120 mg/kg/day. Audiological assessment was performed by the distortion product otoacoustic emission (DPOAE) and auditory brainstem response (ABR) measurements, applied to all rats at the beginning of the study, and also on day 14. Biochemical parameters were calculated on day 14 to evaluate the oxidative and antioxidative status. Their cochleae were removed and examined histopathologically, also on day 14. The cochlea of animals were evaluated with the terminal deoxynucleotidyl transferase-mediated dUTPbiotin nick end labeling (TUNEL) method for apoptosis. Results: On days 14, DPOAE values and ABR thresholds were preserved in group 3(naringenin + gentamicin) when compared with group 2(gentamicin)(p < 0.008). The total oxidant status values and oxidative stress index values were significantly higher in group 2(gentamicin) than in other groups (p < 0.008). The total antioxidant status value was significantly higher in group 3(naringenin + gentamicin) and group 4(naringenin) than in group 2(gentamicin)(p < 0.008). The number of TUNEL positive cells in both the organ of Corti and the stria vascularis were found to be statistically lower in group 3(naringenin + gentamicin) than in group 2(gentamicin)(p < 0.05). Conclusion: Our study has demonstrated that the ototoxic effect generated by gentamicin could be ameliorated with the concurrent use of naringenin. (C) 2017 Elsevier B.V. All rights reserved
Reduced densities of parvalbumin- and somatostatin-expressing interneurons in experimental cortical dysplasia and heterotopia in early postnatal development
Cortical dysplasia (CD) is strongly associated with intractable epilepsy, probably due to hyperexcitability of neuronal networks. However, the underlying mechanisms are not completely understood. GABAergic interneurons provide major inhibitory function in the CNS and have different subtypes, but it is not clear how each subtype is affected in CD during early post-natal development. We have examined the developmental alterations of the densities of two major subtypes of interneurons, parvalbumin (PV)- and somatostatin (SS)-expressing interneurons in an animal model of CD, in utero irradiation, using immunocytochemistry. We found that the density of PV- and SS-positive interneurons increases significantly in CD and controls during the first three weeks of postnatal life. However, compared to controls, the densities of both subtypes are significantly decreased in CD and heterotopia at all age groups although the time of onset for both PV and SS expression remained unchanged. Our results indicate that the densities of both PV- and SS-positive interneurons are significantly decreased in CD and heterotopia, which may be one important mechanism leading to hyperexcitability of CD. Published by Elsevier B.V
Effects of montelukast sodium on tendon healing: An experimental study
Introduction: Montelukast sodium (MS) a selective leukotriene antagonist of the cysteinyl leukotriene receptor, has been used in the treatment of asthma and allergic rhinitis. In this study, we evaluated the effect of MS on the early inflammatory phase (histological) of nonsynovial tendon healing. Materials and Methods: Rats were divided randomly into two groups (n = 6 each). MS (Singulair) was administered to one group at 10 mg/kg/day [250 g/day intraperitoneally (i.p.)]. The control group was administered 250 g/day of 0.9% saline i.p. This nonsynovial tendon was longitudinally divided at the midportion, cut transversely and then sutured. In both groups, the rats were sacrificed by decapitation 10 days later. Results: Decreased inflammatory cell infiltration and more properly oriented collagen fibres were observed in the MS group's histopathological specimens as compared to the control group's (P < 0.05). Additionally, vascularity was decreased in the MS group. Conclusion: MS decreased tendon healing, apparently by inhibiting the early inflammatory phase of nonsynovial tendon healing
The effects of long-term prenatal exposure to 900, 1800, and 2100 MHz electromagnetic field radiation on myocardial tissue of rats
It is well-known that wireless communication technologies facilitate human life. However, the harmful effects of electromagnetic field (EMF) radiation on the human body should not be ignored. In the present study, we evaluated the effects of long-term, prenatal exposure to EMF radiation on the myocardium of rats at varying durations. Overall, 18 pregnant Sprague-Dawley rats were assigned into six groups (n = 3 in each group). In all groups other than the control group, three pregnant rats were exposed to EMF radiation (900, 1800 and 2100 MHz) for 6, 12 and 24 h over 20 days. After delivery, the newborn male pups were identified and six newborn male pups from each group were randomly selected. Then, histopathological and biochemical analysis of myocardial samples were performed. When 24-h/day prenatal exposures to 900, 1800, 2100 MHz EMF radiation were evaluated, myocardial damage was greater in the 2100 MHz EMF-24h group than the other groups. In addition, when malondialdehyde (MDA) and glutathione (GSH) levels associated with reactive oxidative species (ROS) were evaluated, the MDA level was higher in the 2100 MHz EMF-24h group compared with the other groups. The GSH level was also lower in the 2100 MHz EMF-24h group. When the 6, 12 and 24 h/day prenatal exposures to 1800 MHz EMF radiation were evaluated, myocardial damage was greater in 1800 MHz EMF-24h group than the remaining groups (p < 0.0001). Also, MDA level was greater in the 1800 MHz EMF-24h group compared with the other groups while the GSH level was lower in this group. It was shown that myocardial tissue was affected more by long-term exposure to EMF radiation at high frequencies. The data raise concerns that the harmful effects of non-ionizing radiation exposure on cardiac tissue will increase with 5G technology
3-boyutlu biyoyazıcı teknolojisi ile kök hücre yüklü nanohibrit kemik/kıkırdak doku iskelelerinin geliştirilmesi: in vitro ve in vivo değerlendirilmesi
Osteokondral doku hasarı, hastalıktan travmaya kadar farklı nedenlerle ortaya çıkabilen ciddi bir
sağlık sorunudur. Osteokondral arayüz defektleri yaygın olarak hem kıkırdak (hiyalin) hem de destekleyici
subkondral kemiğin lezyonlarını içermektedir. Hasarın ortopedik cerrahi ile fonksiyonel onarımı, osteokondral
yapının karmaşıklığı göz önüne alındığında oldukça zordur. Osteokondral doku mühendisliği, kemik, kıkırdak
ve kemik-kıkırdak arayüzünün onarımı ve yenilenmesi için; yapısal iskelelerin, biyoaktif moleküllerin ve
hücrelerin kullanımı ile bu zorlukların üstesinden gelmeyi amaçlamaktadır. Gözenekli iskeleler, lifler ve
hidrojeller gibi çeşitli matris yapıları, aynı anda kıkırdak, orta kalsifiye kıkırdak ve kemik dokularını restore
etmek için tasarlanmaktadır (Yang ve ark., 2017; Ai ve ark., 2021; Wei ve ark., 2021).Bu çalışmada, 3B-biyoyazıcı
tekniği ile kök hücre yüklü, TGF-ß1 ve rhBMP-2 salımı yapabilen çift-tabakalı nanohibrit hidrojel temelli
doku iskeleleri geliştirilmiştir. Doku iskeleleri 3B-biyobaskı yöntemi ile jelatin metakrilat (GelMA), kitosan
metakrilat (KitMA) ve hidrotermal metot ile üretilen LDH nanopartiküllerinin (çift katmanlı hidroksit
bileşikleri) Irgacure2959 fotobaşlatıcı varlığında yazdırılması ve sonrasında UV ışık altında kürlenmesi ile
hazırlanmıştır. LDH nanopartiküllerine yüklenen TGF-ß1 ve rhBMP-2 sinyal molekülerinin nanopartiküllerden
ve doku iskelelerinden in vitro salım davranışları enzim-bağlı immünosorbent testi (ELISA) ile incelenmiştir.
Fiziksel, kimyasal ve mekaniksel özellikleri karakterize edilen doku iskelelerine enkapsüle edilen kök
hücrelerin canlılığı (canlı/ölü testi), morfolojisi (DAPI/Aktin boyama), gelişimi, proliferasyonu (PrestoBlue
analizi), osteojenik ve kondrojenik farklılaşma özellikleri (immünfloresan boyamalar ve PCR analizleri)
incelenmiştir. Doku iskelelerinin kemik ve kıkırdak onarımına etkisi sıçanlar üzerinde in vivo osteokondral
hasar modelinde değerlendirilmiştir. Tüm sonuçlar birlikte değerlendirildiğinde, geliştirilen nanohibrit
çift-tabakalı platformun osteojenik/kondrojenik farklılaşmayı desteklediği ve osteokondral rejenerasyonu
teşvik ettiği sonucuna varılmıştı
Effect of Bumetanide on Facial Nerve Regeneration in Rat Model
Objective We investigated the effects of bumetanide alone and in combination with dexamethasone on facial nerve regeneration in rats with facial paralysis. Study Design A prospective controlled animal study. Setting An animal laboratory. Subjects and Methods Facial paralysis was induced in 32 Wistar rats that we then divided into 4 groups: group 1, control; group 2, bumetanide; group 3, dexamethasone; group 4, bumetanide and dexamethasone. Electroneurography was performed 1, 2, and 4 weeks later, and nerve regeneration was evaluated by electron and light microscopy and Western blotting in week 4. Results Regarding the comparison between preoperative values and week 4, the latency difference in group 1 (1.25 milliseconds) was significantly higher than those of groups 2 to 4 (0.56, 0.34, and 0.10 milliseconds, respectively;P= .001). The latency increment in groups 2 and 3 was higher than that of group 4 (P= .002 andP= .046) in week 4, whereas groups 2 and 3 did not differ significantly (P= .291). Amplitude difference was not statistically significant from week 4 among all groups (allP >.05). The number of myelinated axons was significantly higher in all treatment groups than in the control group (P= .001). Axon number and intensity were significantly higher in group 4 as compared with groups 2 and 3 (P= .009,P= .005). Conclusion After primary neurorrhaphy, dexamethasone and bumetanide alone promoted nerve recovery based on electrophysiologic and histologic measures. Combination therapy was, however, superior
The effects of inflammatory response associated with traumatic spinal cord injury in cutaneous wound healing and on expression of transforming growth factor-beta1 (TGF-beta(1)) and platelet-derived growth factor (PDGF)-A at the wound site in rats
At the cellular level, spinal cord injury (SCI) provokes an inflammatory response that generates substantial secondary damage within the cord, but also may contribute to its repair. The aim of this study was to investigate the effects of inflammatory response associated with SCI in cutaneous wound healing and on expression of transforming growth factor-beta1 (TGF-beta(1)) and platelet-derived growth factor (PDGF)-A at the wound site in rats. At the 14th day analysis, the mean TGF-beta(1) score in trauma group (I) was significantly lower than that in control group (C) (2.60 +/- 0.90 vs. 3.64 +/- 0.37, respectively; p < 0.05). The mean score for PDGF-A expression in group I was similar to the corresponding value in group C (2.42 +/- 0.74 vs. 2.94 +/- 0.72, respectively). Compared to group C, group I had significantly lower mean scores for epidermal and dermal regeneration, but higher mean scores for granulation tissue thickness and similar scores for angiogenesis. The dermal layer contains diffuse deposition of collagen fibers that are not organised as in control rat skin, and intraepidermal and subepidermal vasocongestion is distinct. Based on the results on the parameters evaluated in the study, experimental SCI in rats results in delay in wound healing and low intensity of TGF-beta(1) in the dorsal wound-tissue specimens
An alginate-poly(acrylamide) hydrogel with TGF-beta 3 loaded nanoparticles for cartilage repair: Biodegradability, biocompatibility and protein adsorption
Current implantable materials are limited in terms of function as native tissue, and there is still no effective clinical treatment to restore articular impairments. Hereby, a functionalized polyacrylamide (PAAm)-alginate (Alg) Double Network (DN) hydrogel acting as an articular-like tissue is developed. These hydrogels sustain their mechanical stability under different temperature (+4 degrees C, 25 degrees C, 40 degrees C) and humidity conditions (60% and 75%) over 3 months. As for the functionalization, transforming growth factor beta-3 (TGF-beta 3) encapsulated (NPTGF-beta 3) and empty poly(lactide-co-glycolide) (PLGA) nanopartides (PLGA NPs) are synthesized by using microfluidic plat-form, wherein the mean particle sizes are determined as 81.94 +/- 92 nm and 126 +/- 4.52 nm with very low poly-dispersity indexes (PDI) of 0.194 and 0.137, respectively. Functionaliza lion process of PAAm-Alg hydrogels with ester-end PLGA NPs is confirmed by MR analysis, and higher viscoelastidty is obtained for functionalized hydrogels. Moreover, cartilage regeneration capability of these hydrogels is evaluated with in vitro and in vivo experiments. Compared with the PAAm-Alg hydrogels, functionalized formulations exhibit a better cell viability. Histological staining, and score distribution confirmed that proposed hydrogels significantly enhance regeneration of cartilage in rats due to stable hydrogel matrix and controlled release of TGF-beta 3. These findings demonstrated that PAAm-Alg hydrogels showed potential for cartilage repair and clinical application. (C) 2021 Elsevier B.V. All rights reserved
Nasal septal turbinate: Cadaveric study
Background: Despite the importance of its location, the functional behavior of the nasal septal turbinate (NST) is still not completely understood. Basic histological knowledge is still lacking. The aim of this study was to describe the histological features of the NST and to compare its morphometric features to those of the adjacent nasal septum and the inferior and middle turbinates. Methods: The study included 50 fresh cadavers. Excisional biopsy specimens of the NST with adjacent posterior septum were collected. In addition, mucosal and submucosal biopsy specimens were taken of the inferior and middle turbinates. Morphometric analysis was performed on five different tissue types: glandular elements, connective tissue stroma, arterial structures, and capillary or venous sinusoids. Results: The mean proportion of venous sinusoids was statistically lower in the nasal septum and NST than in the inferior and middle turbinate. The mean proportion of glandular tissues was higher in the NST than in other regions of the nasal cavity. The mean proportion of arterial tissue was lower in the nasal septum and the NST. Significantly fewer capillary elements were found in the inferior and middle turbinates than in the nasal septum and NST. The mean proportion of connective tissues was lower in the NST than in other regions of the nasal cavity. Conclusion: The similar histopathological cell distribution in the middle and inferior turbinate supported a function as an erectile organ, but the findings for the NST pointed to different functional properties of this region
- …